1. Field of the Invention
The present general inventive concept relates to an image forming device and a method thereof. More particularly, the present general inventive concept relates to an image forming device and a method thereof, which can perform an auto color registration through an efficient use of a plurality of developing units.
2. Description of the Related Art
With the development of electronic technology, peripheral devices, such as a printer, a scanner, and so forth, in addition to a computer, have been actively spread. Recently, color laser printers rather than dot printers or inkjet printers have been actively spread. The color laser printer generally expresses a color image by using toners of four colors, i.e., cyan (C), magenta (M), yellow (Y), and black (K). In order to print a clear image, the color laser printer performs the printing work by toner colors using four organic photoconductive drums (OPC drums). Also, in order to locate the respective color toners at correct positions, a transferring process is performed using a paper transfer belt (PTB) or an intermediate transfer belt (ITB).
On the other hand, in order to express the colors, the toners should be accurately superimposed and transferred to a same position using a plurality of OPC drums and transfer machines. However, as the printing work is continuously performed, the color registration of the color laser printer may be distorted. Accordingly, in order to maintain the quality of an image, it is required to perform an auto color registration (ACR).
An ACR is a correction method for matching relative positions of four colors of CMYK to one another in performing the print work. That is, the ACR is a technique that greatly affects the image quality of the color laser printer, and the image quality becomes better as the ACR is performed in larger quantities and more frequently.
However, when one of C, M, Y, or K developing units has not been installed or toner has been consumed in the image forming device, an error called “CRUM Not Installed” or “Toner Empty Error” occurs. As a result, the print work cannot be performed, or an error occurs during the ACR operation, so that the ACR or printing is not properly performed.
In addition, even in a special case where a user does not desire the use of a specified color, the printing or the ACR is performed with all colors, and this causes an unnecessary consumption of toner.
In addition, in order to perform the ACR once, a specified quantity of toner and time for performing the ACR are required, and thus too frequent performing of the ACR is inefficient. Also, an amount of waste toner is increased due to frequent performing of the ACR.
If an ACR execution condition is satisfied, the conventional image forming device necessarily performs the ACR work. In this case, if the residual quantity of toner is not sufficient, it is impossible to perform an accurate ACR. This causes an unnecessary waste of toner and time.